The receptor tyrosine kinase (RTK)-RAS-phosphoinositide 3-kinase (PI3K) pathway is activated in 88% of GBM tumors (Guha et al., 1997; TCGA, 2008), and in lower grade gliomas, activation is predictive of a poor outcome (McBride et al., 2010). This evidence concerns the gene NTRK1 and glioblastoma.